1. Field of Invention
The present invention relates to a turbocharger having a cooling structure in which a turbine is rotated by an exhaust gas, a compressor operated by the turbine increases the power of an engine by compressing intake air, and the quality of the exhaust gas is improved.
2. Description of Related Art
Turbochargers have been generally used for internal combustion engines, particularly, for the engine of heavy trucks or ships. Recently, those turbochargers are used for vehicles in order to achieve large power from small engines. Further, the turbochargers improve the quality of an exhaust gas by making fuel more completely burn. The general function and design of the turbochargers are known in the art.
The turbochargers include a turbine rotated by an exhaust gas and a compressor operated to compress intake air by the turbine, in which the turbine and the compressor are connected by a shaft. In the turbochargers, heat at about 200 to 800 degrees transfers to a center housing and the shaft, such that the heat transfer by the radiated heat is minimized by mounting a heat shield structure.
There is a method that can minimize heat transfer by manufacturing a heat shield with at least two material layers and a heat insulator and securing a heat insulation air layer in the heat shield, and studies for minimizing heat transfer between housings are still being conducted. For example, there are WO2010123761A2 and WO2009068460A1 in the conventional art.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.